U.S. patent application number 10/115105 was filed with the patent office on 2003-04-17 for electric power conversion apparatus.
This patent application is currently assigned to MITSUBISHI DENKI KABUSHIKI KAISHA. Invention is credited to Maekawa, Hirotoshi, Matsuoka, Syougo.
Application Number | 20030072117 10/115105 |
Document ID | / |
Family ID | 19133331 |
Filed Date | 2003-04-17 |
United States Patent
Application |
20030072117 |
Kind Code |
A1 |
Maekawa, Hirotoshi ; et
al. |
April 17, 2003 |
Electric power conversion apparatus
Abstract
To perform a miniaturization and weight reduction of an electric
power conversion apparatus, and in extension, the miniaturization
of an inverter apparatus itself. In the inverter apparatus which
converts a DC voltage into an AC voltage, a semiconductor device
for electric power conversion, and a drive and protection circuit
which drives and protects this semiconductor device for electric
power conversion, and a power supply circuit which supplies power
to this drive and protection circuit are integrated in the same
module.
Inventors: |
Maekawa, Hirotoshi; (Tokyo,
JP) ; Matsuoka, Syougo; (Tokyo, JP) |
Correspondence
Address: |
SUGHRUE MION, PLLC
2100 PENNSYLVANIA AVENUE, N.W.
WASHINGTON
DC
20037
US
|
Assignee: |
MITSUBISHI DENKI KABUSHIKI
KAISHA
|
Family ID: |
19133331 |
Appl. No.: |
10/115105 |
Filed: |
April 4, 2002 |
Current U.S.
Class: |
361/86 |
Current CPC
Class: |
H01L 2924/13055
20130101; H01L 2924/13055 20130101; H02M 1/08 20130101; H01L
2224/48091 20130101; H01L 2924/13091 20130101; H01L 2924/181
20130101; H01L 2224/48091 20130101; H01L 2924/13091 20130101; H02M
7/003 20130101; H05K 7/1432 20130101; H02M 1/32 20130101; H05K
9/002 20130101; H01L 2224/48137 20130101; H01L 2924/181 20130101;
H01L 2924/00 20130101; H01L 2924/00 20130101; H01L 2924/00012
20130101; H01L 2924/00014 20130101 |
Class at
Publication: |
361/86 |
International
Class: |
H02H 003/18 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 12, 2001 |
JP |
2001-315113 |
Claims
What is claimed is:
1. In an inverter apparatus for converting a DC voltage into an AC
voltage, an electric power conversion apparatus, wherein
semiconductor device for electric power conversion, drive and
protection means for driving and protecting the semiconductor
device for an electric power conversion, a power circuit supplying
electric power to the drive and protection means are integrated in
one module.
2. The electric power conversion apparatus according to claim 1,
wherein said drive and protection means and said power circuit are
mixedly mounted on both sides of a board, and a metal shielding
plate is arranged between the board and the semiconductor device
for electric power conversion.
3. The electric power conversion apparatus according to claim 2,
wherein a board on which said drive and protection means and said
power circuit are mixedly mounted is made to be a multilayer board,
and heat generated in an inner layer pattern of the board is made
to be radiated through the metal shielding plate to a base plate
connected to an external cooler.
4. The electric power conversion apparatus according to claim 3,
wherein a low profile type sheet transformer made by combining
ferrite core material and a multilayer board is used as a switching
transformer in the power circuit.
5. The electric power conversion apparatus according to claim 1,
wherein said drive and protection means comprises: a diode device
incorporated in the semiconductor device for electric power
conversion; a constant current circuit which gives a constant
current to the diode device; an waveform shaping circuit which
shapes a waveform of a voltage between both ends of the diode
device; and a microcomputer which fetches a voltage between both
ends of the diode device whose waveform is shaped, and the
semiconductor device for electric power conversion is shut off on
the basis of the voltage between both ends of the diode device,
which is fetched, and overheat determination temperature data
stored beforehand.
6. The electric power conversion apparatus according to claim 5,
wherein the microcomputer has correcting operation means for
performing correcting operation of a temperature map at the time of
product shipment, and storing the overheat determination
temperature data beforehand, interpolating operation means for
performing interpolating operation on the basis of the overheat
determination temperature data and a detection output of a
temperature detecting element on a board during normal
operation.
7. The electric power conversion apparatus according to claim 1,
wherein said drive and protection means comprises: a sensing
terminal which takes out a shunt current of the semiconductor
device for electric power conversion, conversion means for
converting the shunt current into a voltage; and short-circuit
current detection means for comparing a voltage from the conversion
means with a voltage equivalent to a short-circuit current of the
semiconductor device for electric power conversion, and the
semiconductor device for electric power conversion is shut off on
the basis of the comparison result of the short-circuit current
detection means.
8. The electric power conversion apparatus according to claim 1,
wherein said drive and protection means comprises: a sensing
terminal which takes out a shunt current of the semiconductor
device for electric power conversion; conversion means for
converting the shunt current into a voltage; overcurrent detection
means for comparing a voltage from the conversion means with a
voltage equivalent to an overcurrent of the semiconductor device
for electric power conversion, and di/dt of the semiconductor
device for electric power conversion is suppressed without shutting
off switching operation on the basis of comparison result of the
overcurrent detection means.
9. The electric power conversion apparatus according to claim 1,
wherein said drive and protection means comprises: gate
short-circuit detection means for comparing a logic level of a gate
input signal for driving the semiconductor device for electric
power conversion with a logic level of a gate terminal voltage of
the semiconductor device for the electric power conversion, and
when comparison result of the gate short-circuit detection means is
negative, the semiconductor device for electric power conversion is
shut off.
10. The electric power conversion apparatus according to claim 1,
wherein said drive and protection means comprises: gate voltage
abnormality determination means for comparing a gate voltage of a
gate of the semiconductor device for electric power conversion with
a voltage for gate voltage abnormality determination, and the
semiconductor device for electric power conversion is shut off on
the basis of comparison result of the gate voltage abnormality
determination means.
11. The electric power conversion apparatus according to claim 5,
wherein said drive and protection means suppresses di/dt of the
semiconductor device for electric power conversion when the
semiconductor device is shut off.
12. The electric power conversion apparatus according to claim 8,
wherein, when the semiconductor device for electric power
conversion is shut off, said drive and protection means
simultaneously shuts off all the gate input signals of
semiconductor devices other than the concerned semiconductor
device, and also outputs to an external control unit which
protective function shuts off the semiconductor device.
13. The electric power conversion apparatus according to claim 1,
further comprising a voltage dividing circuit which divides a high
power supply voltage; a microcomputer which shapes in a waveform a
voltage divided by the voltage dividing circuit and performs A/D
conversion processing, and performs map interpolating operation of
the A/D converted value, and output means for converting
calculation result of the microcomputer into a voltage level on the
basis of a low voltage power supply reference, and outputting it to
an external control unit as a voltage value of a high voltage power
supply.
14. The electric power conversion apparatus according to claim 13,
further comprising adjusting means for performing correcting
operation of a voltage map before product shipment; and making A/D
conversion map data of a divided voltage of a high power supply
voltage stored in the microcomputer beforehand.
15. The electric power conversion apparatus according to claim 13,
wherein said microcomputer has overvoltage determination means for
comparing overvoltage data, stored beforehand, with an
A/D-converted value of a divided voltage of the high power supply
voltage, and wherein, if exceeding an overvoltage level, with
suppressing and shutting off di/dt of the semiconductor device for
electric power conversion, the microcomputer outputs to an external
control unit that the semiconductor device for the electric power
conversion is shut off.
Description
[0001] This application is based on Application No. 2001-315113,
filed in Japan on Oct. 12, 2001, the contents of which are hereby
incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to an electric power conversion
apparatus used for an electric vehicle driving apparatus or an
inverter apparatus, and in particular, to structure for
miniaturization and weight reduction, and advanced functionality of
drive and protection means of a semiconductor device for electric
power conversion, failure diagnosis, or the like.
[0004] 2. Description of the Related Art
[0005] In the electric vehicle, in particular, an electric
motorcar, or a hybrid car, the miniaturization and weight reduction
of an inverter apparatus for three-phase motor drive are required
for a mounting space and fuel cost reduction. Generally, an
inverter apparatus consists of an electric power conversion
apparatus for converting a DC voltage into an AC voltage, and a
controller that controls a three-phase motor. Usually, they are
contained in separate cases respectively due to problems of heat
generation and switching noise of the semiconductor device for
electric power conversion.
[0006] As for the electric power conversion apparatus, an
intelligent module where a high-speed semiconductor device
represented by an IGBT and a circuit for driving and protecting the
IGBT are integrated has been already produced commercially. For
example, as shown in Japanese Patent Laid-Open No. 5-137339, the
structure of arranging an IGBT drive and protection circuit board
on a semiconductor device is disclosed.
[0007] In addition, as for a controller, a high-performance
microcomputer is usually used, and arbitrarily controls the
rotation speed, torque, and electric power of a three phase motor
by inputting a line current, a rotating speed, etc. of the three
phase motor from dedicated sensors and performing data processing,
and giving a switching signal to a gate terminal of a semiconductor
device in the electric power conversion apparatus. In addition,
although a pulse width modulation waveform called PWM is used as a
switching signal waveform given to a gate terminal of a
semiconductor device for electric power conversion, since it is
general technique, detailed explanation will be omitted here.
[0008] In the configuration of a conventional inverter apparatus,
as shown in FIG. 18, an electric power conversion apparatus 123
including a signal insulation circuit 115a and a U phase arm
typically showing only one phase of three phases, and a controller
121 including a microcomputer 114a etc. are respectively contained
in separate cases. However, a power supply 122 supplying power to
an IGBT drive and protection circuit board is also contained in a
case different from these due to problems of heat generation and
noise. In addition, the U phase arm includes a UH phase (upper arm
U phase) drive and protection circuit 117a, a UL phase (lower arm U
phase) drive and protection circuit 118a, and switching devices 2a
and 2b and free wheel diodes 3a and 3b as electric power conversion
devices. Reference numeral 20 is a three-phase motor.
[0009] The power supply 122 which includes an waveform shaping
circuit 26 and an insulation type power supply circuit 116a and
supplies power to an IGBT drive and protection circuit board may be
integrated in an IGBT drive and protection circuit board in an
intelligent module in the case of that with comparatively small
power capacity. Nevertheless, since the current capacity of the
power supply circuit itself also becomes large in that with large
power capacity, the power supply circuit is contained in a case
different from an intelligent module due to a cooling method of
suppressing heat generation of a power transformer etc., and a
problem of a board mounting space.
[0010] In addition, since a malfunction of an electronic component
mounted on the board is induced due to the influence of
electromagnetic noise at the time of IGBT performing switching
operation, it is devised to simply obtain the effect of
electromagnetic shielding in a conventional IGBT drive and
protection circuit board by arranging all the electronic components
on the top surface (C side) of the board and making the back
surface (S side) fully grounded. On the other hand, since only one
side of the board becomes the mounting space of electronic
components, this becomes a struggle of raising a degree of
integration and functions of the IGBT drive and protection
circuit.
[0011] As described above, a power supply of an IGBT drive and
protection circuit cannot be integrated with an intelligent module
in a conventional apparatus due to problems of heat generation and
switching noise of a semiconductor device, and a board mounting
space. Hence, there is a disadvantage that it is not possible to
miniaturize an electric power conversion apparatus, and in
extension, an inverter apparatus itself.
BRIEF SUMMARY OF THE INVENTION
[0012] This invention is achieved to solve the above problems, and
its object is to provide an electric power conversion apparatus
that is miniaturized and reduced in weight by integrating not only
an IGBT drive and protection circuit but also a power supply
circuit for supplying power into a conventional intelligent module
which is an electric power conversion circuit. That is, its object
is not only to perform the miniaturization and weight reduction of
the inverter apparatus, but also to obtain an electric power
conversion apparatus that is highly reliable, sophisticated, and
excellent in safety, by mixedly arranging the power supply circuit
and other functions in the electric power conversion apparatus,
i.e., a conventional intelligent module.
[0013] The above-described power supply circuit is prepared for
every reference electric potential of each IGBT device, and is
electrically insulated completely from a low voltage power supply
system. Therefore, it becomes possible to collect a high voltage
system in an intelligent module by integrating a power supply
circuit into an electric power conversion apparatus. Hence, since
it is electrically separable from a low voltage power supply
system, it is possible to provide ideal configuration in a safety
aspect for applications in an electric motorcar etc.
[0014] In addition, another object is to provide an electric power
conversion apparatus with not only a conventional IGBT drive and
protective function, but also diagnostic functions such as an alarm
signal and failure history, and a high value-added function such as
trimming adjustment of a semiconductor device protection circuit
for electric power conversion by mixedly mounting not only the
above-described power supply circuit, but also a digital control
circuit using a microcomputer through increasing an electronic
component mounting space by implementing the multilayer structure
and double-sided mounting of a board in the electric power
conversion apparatus.
[0015] An electric power conversion apparatus according to the
present invention as claimed in claim 1 is an apparatus where, in
an inverter apparatus which converts a DC voltage into an AC
voltage, a semiconductor device for electric power conversion,
drive and protection means for driving and protecting the
semiconductor device for an electric power conversion, and a power
circuit supplying electric power to the drive and protection means
are integrated in one module.
[0016] The electric power conversion apparatus according to the
present invention as claimed in claim 2 is an apparatus where the
drive and protection means and the power circuit are mixedly
mounted on both sides of a board, and a metal shielding plate is
arranged between the board and the semiconductor device for
electric power conversion.
[0017] The electric power conversion apparatus according to the
present invention as claimed in claim 3 is an apparatus where a
board on which the drive and protection means and the power circuit
are mixedly mounted is made to be a multilayer board, and heat
generated in an inner layer pattern of the board is made to be
radiated through the metal shielding plate to a base plate
connected to an external cooler.
[0018] The electric power conversion apparatus according to the
present invention as claimed in claim 4 is an apparatus where a low
profile type sheet transformer made by combining ferrite core
material and a multilayer board is used as a switching transformer
in the power circuit.
[0019] The electric power conversion apparatus according to the
present invention as claimed in claim 5 is an apparatus where the
drive and protection means includes a diode device incorporated in
the semiconductor device for electric power conversion, a constant
current circuit which gives a constant current to the diode device,
an waveform shaping circuit which shapes a waveform of a voltage
between both ends of the diode device, and a microcomputer which
fetches a voltage between both ends of the diode device whose
waveform is shaped, and where the semiconductor device for electric
power conversion is shut off on the basis of the voltage between
both ends of the diode device, which is fetched, and overheat
determination temperature data stored beforehand.
[0020] The electric power conversion apparatus according to the
present invention as claimed in claim 6 is an apparatus where the
microcomputer has correcting operation means for performing
correcting operation of a temperature map at the time of product
shipment, and storing the overheat determination temperature data
beforehand, interpolating operation means for performing
interpolating operation on the basis of the overheat determination
temperature data and a detection output of a temperature detecting
element on a board during normal operation.
[0021] The electric power conversion apparatus according to the
present invention as claimed in claim 7 is an apparatus where the
drive and protection means includes a sensing terminal which takes
out a shunt current of the semiconductor device for electric power
conversion, conversion means for converting the shunt current into
a voltage, and short-circuit current detection means for comparing
a voltage from the conversion means with a voltage equivalent to a
short-circuit current of the semiconductor device for electric
power conversion, and where the semiconductor device for electric
power conversion is shut off on the basis of the comparison result
of the short-circuit current detection means.
[0022] The electric power conversion apparatus according to the
present invention as claimed in claim 8 is an apparatus where the
drive and protection means includes a sensing terminal which takes
out a shunt current of the semiconductor device for electric power
conversion, conversion means for converting the shunt current into
a voltage, overcurrent detection means for comparing a voltage from
the conversion means with a voltage equivalent to an overcurrent of
the semiconductor device for electric power conversion, and where
di/dt of the semiconductor device for electric power conversion is
suppressed without shutting off switching operation on the basis of
comparison result of the overcurrent detection means.
[0023] The electric power conversion apparatus according to the
present invention as claimed in claim 9 is an apparatus where the
drive and protection means includes gate short-circuit detection
means for comparing a logic level of a gate input signal for
driving the semiconductor device for electric power conversion with
a logic level of a gate terminal voltage of the semiconductor
device for the electric power conversion, and where, if comparison
result of the gate short-circuit detection means is negative, the
semiconductor device for electric power conversion is shut off.
[0024] The electric power conversion apparatus according to the
present invention as claimed in claim 10 is an apparatus where the
drive and protection means includes gate voltage abnormality
determination means for comparing a gate voltage of a gate of the
semiconductor device for electric power conversion with a voltage
for gate voltage abnormality determination, and where the
semiconductor device for electric power conversion is shut off on
the basis of comparison result of the gate voltage abnormality
determination means.
[0025] The electric power conversion apparatus according to the
present invention as claimed in claim 11 is an apparatus where the
drive and protection means suppresses di/dt of the semiconductor
device for electric power conversion when the semiconductor device
is shut off.
[0026] The electric power conversion apparatus according to the
present invention as claimed in claim 12 is an apparatus where,
when the semiconductor device for electric power conversion is shut
off, the drive and protection means simultaneously shuts off all
the gate input signals of semiconductor devices other than the
concerned semiconductor device, and also outputs to an external
control unit what protective function shuts off the semiconductor
device.
[0027] The electric power conversion apparatus according to the
present invention as claimed in claim 13 is an apparatus further
including a voltage dividing circuit which divides a high power
supply voltage, a microcomputer which performs waveform shaping of
a voltage divided by the voltage dividing circuit and performs A/D
conversion processing, and performs map interpolating operation of
the A/D converted value, output means for converting calculation
result of the microcomputer into a voltage level on the basis of a
low voltage power supply, and outputting it to an external control
unit as a voltage value of a high voltage power supply.
[0028] The electric power conversion apparatus according to the
present invention as claimed in claim 14 is an apparatus further
including adjustment means for performing correcting operation of a
voltage map before product shipment, and making A/D conversion map
data of a divided voltage of a high power supply voltage stored in
the microcomputer beforehand.
[0029] The electric power conversion apparatus according to the
present invention as claimed in claim 15 is an apparatus where the
microcomputer has overvoltage determination means for comparing
overvoltage data, stored beforehand, with an A/D-converted value of
a divided voltage of the high power supply voltage, and where, if
exceeding an overvoltage level, with suppressing and shutting off
di/dt of the semiconductor device for electric power conversion,
the microcomputer outputs to an external control unit that the
semiconductor device for the electric power conversion is shut
off.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 is a block diagram showing a circuit configuration of
an electric power conversion apparatus according to a first
embodiment of the present invention;
[0031] FIG. 2 is a side elevation showing an internal configuration
of the electric power conversion apparatus according to the first
embodiment of this invention;
[0032] FIG. 3 is a sectional view showing an internal configuration
of an electric power conversion apparatus according to a second
embodiment of this invention;
[0033] FIG. 4 is a side view showing a low profile type transformer
used in an electric power conversion apparatus according to a
fourth embodiment of the present invention;
[0034] FIG. 5 is a block diagram showing a circuit configuration of
an electric power conversion apparatus according to a fifth
embodiment of this invention;
[0035] FIG. 6 is a graph showing examples of Vf-if characteristics
of diodes for temperature detection used for the electric power
conversion apparatus according to the fifth embodiment of this
invention;
[0036] FIG. 7 is a graph showing examples of Tj-Vf characteristics
of diodes for temperature detection used for the electric power
conversion apparatus according to the fifth embodiment of this
invention;
[0037] FIG. 8 is a block diagram showing a circuit configuration of
an electric power conversion apparatus according to a sixth
embodiment of this invention;
[0038] FIG. 9 is a side elevation showing an example of a method of
detecting base plate temperature of the electric power conversion
apparatus according to the sixth embodiment of this invention;
[0039] FIG. 10 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to a seventh
embodiment of the present invention;
[0040] FIG. 11 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to an eighth
embodiment of this invention;
[0041] FIG. 12 includes examples of operating waveforms of the
electric power conversion apparatus according to the eighth
embodiment of this invention;
[0042] FIG. 13 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to a ninth
embodiment of this invention;
[0043] FIG. 14 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to a tenth
embodiment of the present invention;
[0044] FIG. 15 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to a twelfth
embodiment of the present invention;
[0045] FIG. 16 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to thirteenth
and fifteenth embodiments of the present invention;
[0046] FIG. 17 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to a fourteenth
embodiment of the present invention; and
[0047] FIG. 18 is a block diagram showing a circuit configuration
of an inverter apparatus including a conventional electric power
conversion apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0048] Hereafter, an embodiment of this invention will be described
on the basis of drawings. In addition, the same symbols as those in
FIG. 18 shows the same or corresponding portions in the drawings.
In addition, the basic operation of an electric power conversion
apparatus will be omitted since it is the same or similar to what
is generally called an inverter. Nevertheless, about the notation
of a semiconductor device for electric power conversion, a device
which stands in a higher potential (P) side of a DC power input
(between P-N in the drawing) is called an upper arm device, and a
device which stands in a lower potential (N) side is called a lower
arm device.
[0049] Embodiment 1
[0050] FIG. 1 is a block diagram showing a circuit configuration of
an electric power conversion apparatus according to a first
embodiment of the present invention.
[0051] In FIG. 1, reference numeral 19 denoted an electric power
conversion apparatus, reference numeral 20 denotes a three phase
motor, reference numeral 111 denotes a control circuit including a
microcomputer 114b etc., reference numeral 112 denotes a power
supply circuit which includes a waveform shaping circuit 26 and an
insulation type power supply circuit 116b, and supplies power to an
IGBT drive and protection circuit board, and reference numeral 113
denotes an electric power conversion circuit including a signal
insulation circuit 115b and a U phase arm which typically indicates
only one phase of three phases. In addition, the U phase arm
includes a UH phase drive and protection circuit 117b and a UL
phase drive and protection circuit 118b as drive and protection
means, and switching devices 2a and 2b and the free wheel diodes 3a
and 3b as semiconductor devices for electric power conversion.
[0052] The microcomputer 114b of the control circuit 111 generates
a switching signal on the basis of information from the external so
as to drive the semiconductor devices for electric power
conversion. This switching signal is electrically separated by the
insulation type power supply circuit 116b and signal insulation
circuit 115b from the low voltage power supply system where the
microcomputer 114b operates, and is also transmitted to gate
terminals of respective upper and lower arm devices in U, V, and W
phases that are mutually separated electrically. Here, it is
arbitrary whether the above-described switching signal is generated
inside the electric power conversion apparatus 19 or it is given
from an external controller not shown.
[0053] FIG. 2 is a sectional view showing an internal configuration
of the electric power conversion apparatus according to a first
embodiment of this invention.
[0054] In FIG. 2, reference numeral 1 denotes a main board
(hereinafter, only a PCB) where the control circuit 111, power
supply circuit 112, electric power conversion circuit 113, or the
like are mounted except the above-described semiconductor devices
for electric power conversion (the switching devices 2 and free
wheel diodes 3). In addition, reference numeral 4 denotes a metal
shielding plate, reference numeral 5 denotes wiring for connecting
the control circuit board, reference numeral 6 denotes a connecting
conductor, reference numeral 7 denotes an insulated board,
reference numeral 8 denotes a switching power module base plate,
reference numeral 9 denotes a gel-like filler, reference numeral 10
denotes an electrode bus bar for external connection, reference
numeral 11 denotes a switching power module case, and reference
numeral 12 denotes a case.
[0055] A circuit for the driving and protecting semiconductor
devices for electric power conversion, a power supply circuit which
supplies power to this circuit for driving and protecting
semiconductor devices, and an interface circuit for external
connection (control circuit) are mounted on the PCB 1. Here, the
PCB 1 does not restrain the difference between one-sided mounting
and double-sided mounting of components, the quality of material of
a board, geometry, etc. On the other hand, a semiconductor device
is arranged through the insulated board 7, installed for the
purpose of electric insulation, on the base plate 8 for forming the
outline of a product and also connecting the semiconductor devices
with a cooler not shown. In addition, in the case 11 the electrode
bus bar 10 for external connection and the control circuit board
connection wiring 5 are molded in one piece, and the case 11 is
joined with the base plate 8. Furthermore, the semiconductor
devices, electrode bus bar 10, and control circuit board connection
wiring 5 are electrically connected by the connection conductor 6,
and the PCB 1 is electrically connected by the control circuit
board connection wiring 5.
[0056] Thus, in this embodiment, a power supply circuit which
supplies power to a circuit for driving and protecting
semiconductor devices for electric power conversion is mixedly
mounted on a board in which the circuit for driving and protecting
semiconductor devices is mounted, and the board is integrated with
the semiconductor devices for electric power conversion in one
module. Hence, it becomes possible to perform the miniaturization
and weight reduction of an electric power conversion apparatus, and
in extension, the miniaturization of the inverter apparatus itself.
In addition, as long as being a semiconductor device for high-speed
switching, the semiconductor device such as MOSFET other than an
IGBT can be used as the semiconductor device for electric power
conversion.
[0057] Embodiment 2
[0058] FIG. 3 is a sectional view showing an internal configuration
of an electric power conversion apparatus according to a second
embodiment of this invention.
[0059] In addition to the configuration of the above-described
first embodiment, for example as shown in FIG. 3, this embodiment
is to together fasten the PCB1 and metal shielding plate 4 with
using each screw 13a for fixing the PCB1 to the switching power
module case 11, and to obtain electric connection with the metal
shielding plate 4 and base plate 8 through each insert nut 14
molded with the switching power module case 11 in one piece.
[0060] That is, in order to secure a parts mounting space in the
board, the board, i.e., PCB 1, where the circuit that drives and
protects the semiconductor devices for electric power conversion,
and the power supply circuit are mixedly mounted, is made to be a
double-sided one. Hence, in order to obtain noise reduction
effectiveness equal to or better than a fully-grounded pattern on
the back face of the board that is conventional art, the metal
shielding plate 4 (S side) with low permeability in a switching
frequency band is arranged between the board and the semiconductor
devices for electric power conversion is arranged.
[0061] Thus, in this embodiment, since the base plate 8 is used in
a state where the base plate 8 is connected with the cooler not
shown, it becomes possible to effectively reduce the influence of
electromagnetic noise to the PCB 1 by stabilizing the cooler, which
mainly consists of metal, in electric potential. Hence, the fully
grounded pattern such as a conventional IGBT drive and protection
circuit board becomes unnecessary. In consequence, it becomes easy
to achieve the double-sided mounting of the PCB 1, and hence this
contributes to the miniaturization of an apparatus.
[0062] Embodiment 3
[0063] In this embodiment, in addition to the above-described
second embodiment, the PCB 1 is made to be substantially
multilayer, and a fully-grounded pattern on an internal layer is
connected with the base plate 8 electrically and thermally through
the metal shielding plate 4 and the insert nut 14.
[0064] Thus, in this embodiment, a heavily heating component is
made to radiate heat to the base plate 8 connected to an external
cooler through an inner layer pattern and the metal shielding plate
4 by making a board, where a circuit which drives and protects
semiconductor devices for electric power conversion, and a power
supply circuit are mixedly mounted, be a multilayer board,
connecting the inner layer pattern of the board to a lead portion
of the heavily heating component, and together fastening the metal
shielding plate 4 with the board through the inner layer pattern at
multiple points. Hence, it is possible to improve the cooling
effect of the PCB 1 and to suppress temperature rise inside the
electric power conversion apparatus.
[0065] Embodiment 4
[0066] FIG. 4 is a side elevation showing a low profile type
transformer used for an electric power conversion apparatus
according to a fourth embodiment of this invention.
[0067] This embodiment uses, for example, a low profile type sheet
transformer, which has a form shown in FIG. 4 and is made by
combining ferrite core material 15 and a multilayer board 16, as a
switching transformer of a power supply circuit which supplies
power to a circuit for driving and protecting semiconductor devices
for electric power conversion.
[0068] Thus, in this embodiment, in order to perform the
miniaturization and weight reduction of a power supply circuit
which supplies power to a circuit for driving and protecting
semiconductor devices for electric power conversion, a sheet
transformer that complies with surface mount specifications and is
made by combining ferrite core material and a multilayer board is
provided instead of a bobbin core type transformer which is
conventional art. Hence, since an insulation type power supply
circuit in the low profile structure which can be used under an
environment where antivibration conditions are severe, such as a
vehicle-mounting application is constituted, it is possible not
only to obtain a power supply with comparatively large capacity,
but also to achieve the miniaturization and weight reduction.
[0069] Embodiment 5
[0070] FIG. 5 is a block diagram showing a circuit configuration of
an electric power conversion apparatus according to a fifth
embodiment of this invention. In addition, in FIG. 5, the same
numerals will be given to parts corresponding to those in FIG. 1,
and the description on them will be omitted. In addition, here, a
case that a switching signal for driving a semiconductor device for
electric power conversion is given from an external controller not
shown is described.
[0071] In this drawing, reference numerals 21a and 21b denote gate
signal switching devices, reference numeral 22 denotes a waveform
shaping circuit, reference numeral 23 denotes overheat
identification means, reference numeral 24 denotes overheat
determination temperature storage means, reference numeral 25
denotes overheat protection means, reference numeral 26 denotes a
gate drive signal waveform shaping circuit, reference numeral 27
denotes a temperature detection diode, and reference numeral 28 is
a constant current circuit. In addition, the gate signal switching
devices 21a and 21b, and the gate drive signal waveform shaping
circuit 26 substantially constitute a driving portion of drive and
protection means, and circuits from the waveform shaping circuit 22
to the overheat protection means 25 substantially constitute a
protection portion of the drive and protection means. In addition,
the overheat identification means 23, the overheat determination
temperature storage means 24, and the overheat protection means 25
constitute a microcomputer.
[0072] Next, operation will be described.
[0073] When current is flown by electric power conversion operation
(switching) to the semiconductor device 2 or 3 for electric power
conversion, heat is generated by the internal loss of the
semiconductor devices. If the semiconductor device generates heat
too much, there is a possibility that the device may be broken due
to overheat. Therefore, the overheat identification means 23
detects the temperature of the semiconductor device, and determines
whether a gate signal is shut off (gate cut) for overheat
protection. If determining to perform the gate cut, the overheat
identification means 23 transmits a signal to the overheat
protection means 25. The overheat protection means 25 receives this
signal, and shuts off the transfer of the gate signal from the gate
drive signal waveform shaping circuit 26 to the semiconductor
devices 2a and 2b with controlling the gate signal switching
devices 21a and 21b.
[0074] Temperature detection of the semiconductor devices in the
overheat identification means 23 is specifically made as follows.
First, as a temperature sensor for the semiconductor devices, a
temperature detection diode 27 is formed and arranged on the same
board as the semiconductor devices. The constant current circuit 28
is connected to the temperature detection diode 27. A fixed current
"if" which flows from the constant current circuit 28 flows into an
anode of the temperature detection diode 27, and flows out from a
cathode. The flowing current at this time is called a forward
current from the polarity at the time of flowing into the
temperature detection diode 27. In addition, the potential
difference generated between the anode and cathode of the
temperature detection diode 27 is called forward voltage Vf. An
overheat identification means 23 inputs the forward voltage Vf
through the waveform shaping circuit 22 connected to the anode and
cathode of the temperature detection diode 27.
[0075] Here, between the forward voltage Vf of a diode, and the
forward current "if", the characteristic shown in FIG. 6 holds
because of physical property. Thus, depending on the junction
temperature Tj of the diode, the forward voltage Vf to the forward
current "if" varies. The direction of the variation is the
direction of lowering the forward voltage Vf to the rise of the
junction temperature Tj.
[0076] In addition, the forward voltage Vf at the time when the
fixed forward current "if" flows in a diode has the characteristic
shown in FIG. 7 to the junction temperature Tj. Thus, the forward
voltage Vf decreases to the junction temperature Tj rising.
Therefore, if the variation of the forward voltage Vf of the diode
by which a fixed forward current is flown is read, a change of the
junction temperature Tj of the diode is detectable.
[0077] That is, the overheat identification means 23 inputs the
forward voltage Vf of the temperature detection diode 27, and
recognizes the variation of the junction temperature Tj of the
temperature detection diode 27. At this time, by forming the
temperature detection diode 27 near the semiconductor device and
setting the magnitude of the forward current "if" of the
temperature detection diode 27 at the low value at which the diode
itself does not overheat, it is possible to read the junction
temperature Tj of the temperature detection diode 27 as the
junction temperature of the semiconductor device. The overheat
identification means 23 determines whether overheat protection
should be performed, by comparing the junction temperature Tj with
the overheat determination temperature beforehand stored in the
overheat determination temperature storage means 24.
[0078] Although a temperature sensing element such as a thermistor
is stuck on an insulated board in conventional technology, this
embodiment has an on-chip temperature sensor using the
temperature-Vf characteristic of a diode device incorporated on a
semiconductor device as an overheat protective function of the
semiconductor device for electric power conversion in this manner.
In addition, by constituting the temperature sensor for the
semiconductor device for electric power conversion which has a
minimum temperature difference from the core temperature of the
semiconductor device for electric power conversion and is excellent
in the temperature followingness, this embodiment realizes a highly
precise overheat protective function by interpolating operation
means in a microcomputer. That is, by flowing a fixed forward
current in the diode formed on the same board that the
semiconductor device for electric power conversion is formed, and
reading the forward voltage of the diode, it becomes possible to
recognize the temperature of the semiconductor device. Since this
temperature detection responses far quickly than temperature
detection by a thermistor conventionally used, it becomes possible
to improve the overheat protection characteristic of the
semiconductor device by detecting the temperature rise of the
semiconductor device with sufficient accuracy in a short time.
[0079] Embodiment 6
[0080] FIG. 8 is a block diagram showing a circuit configuration of
an electric power conversion apparatus according to a sixth
embodiment of this invention. In addition, in FIG. 8, the same
numerals will be given to parts corresponding to those in FIG. 5,
and the description on them will be omitted.
[0081] In the drawing, reference numeral 29 denotes overheat
determination temperature correction means as interpolating
operation means, reference numeral 30 denotes a board temperature
sensor, reference numeral 31 denotes an adjusting device, reference
numeral 32 denotes temperature measurement means, reference numeral
33 denotes stored-data update means as correcting operation means,
and reference numeral 34 denotes a surface temperature sensor.
[0082] The adjusting device 31 is one of testing equipment
connected at an outgoing inspection step of the electric power
conversion apparatus 19, and during test execution, exchanges
information with the stored-data update means 33 with using the
serial communication means not shown.
[0083] FIG. 9 is a side elevation showing an example of a method of
detecting base plate temperature of the electric power conversion
apparatus according to the sixth embodiment of this invention.
[0084] In the drawing, reference numeral 34 denotes surface
temperature sensors, which are equivalent to the sensors 34a, 34b,
and 34c in FIG. 8. The surface temperature sensors 34 are
respectively arranged so that the temperature of the base plate 8
just under portions, where the maximum temperature of the
semiconductor devices 2 in the lower arm side which incorporate the
temperature detection diodes 27 for respective U, V, and W phases,
can be measured. Reference numeral 35 denotes a test instrument
tool where a heater that is not shown and uniformly warms the base
plate 8 of the electric power conversion apparatus 19 is
incorporated. The test instrument tool is controlled for
temperature so that the semiconductor devices 2 may become constant
temperature by the adjusting device 31. In the electric power
conversion apparatus 19 that becomes an object of the test,
correlation with the temperature of the base plate 8 and the
junction temperature of the semiconductor devices 2 is managed
separately. Although the method of managing temperature correlation
is omitted, the learning adjustment step in the test step at the
time of shipping this product is performed two times under ordinary
temperature and elevated temperature to all the U, V, and W
phases.
[0085] In FIG. 8, a method of operating temperature map correction
will be described in the case of the U phase arm.
[0086] First, by the temperature measurement means 32, the
adjusting device 31 reads the temperature Tcold of the surface
temperature sensor 34a under the ordinary temperature, and
transmits temperature information to the stored-data update means
33 of the electric power conversion apparatus 19 with combining the
temperature Tcold with the information on phase identification. The
stored-data update means 33 stores the temperature Tcold of the
base plate 8 and the forward voltage Vfcold of the temperature
detection diode 27, which are transmitted from the adjusting device
31.
[0087] Next, the temperature Thot of the surface temperature sensor
34a under the elevated temperature is read, and temperature
information is similarly transmitted to the stored-data update
means 33. The stored-data update means 33 obtains the temperature
Thot of the base plate 8 and the forward voltage Vfhot of the
temperature detection diode 27, which are transmitted from the
adjusting device 31, and obtains the following gradient (dT/dV) of
the Tj-Vf characteristic of the U phase arm from these four
parameters.
dT/dV=(Thot-Tcold)/(Vfhot-Vfcold)
[0088] For example, it is apparent that the stored-data update
means 33 can calculate the above-mentioned junction temperature Tj
from the forward voltage Vf of the temperature detection diode 27,
which is read in the normal operation, with using the following
formula by making the overheat determination temperature storage
means 24 store the above-described Tcold, Vfcold, and dT/dV.
Tj=(Vf-Vfcold).times.(dT/dV)+Tcold
[0089] Furthermore, the board temperature sensor 30 for measuring
the temperature of the board (PCB 1) is mounted in the PCB 1 of the
electric power conversion apparatus 19, which the overheat
determination temperature correction means 29 reads as temperature
information. During the usual operation, the overheat determination
temperature correction means 29 measures the temperature on the
board, calculates the variation amount of the above-mentioned dT/dV
as an operation multiplier Kd from a temperature drift correction
map for the on-board electronic components which will not be
described here and is stored beforehand, corrects the
above-mentioned junction temperature Tj with the following formula,
and obtains highly precise junction temperature Tj'.
Tj'=Tj.times.Kd
[0090] Thus, in this embodiment, in order to correct the
characteristic dispersion of the temperature detection diode 27 as
a diode device, by storing beforehand a Vf voltage of the diode
device under conditions of the ordinary temperature and elevated
temperature in the microcomputer in the electric power conversion
apparatus at the time of product shipment, performing the
interpolating operation of the actual device temperature from its
gradient (dT/dV), and further making a value of the temperature
sensing element on the board (for example, thermistor)
coefficient-operated for the temperature drift correction of
on-board electronic components, it becomes possible to detect
temperature highly precisely even under the environment of a wide
temperature range like a vehicle-mounted application.
[0091] Embodiment 7
[0092] FIG. 10 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to a seventh
embodiment of this invention. In addition, in FIG. 10, the same
numerals will be given to parts corresponding to those in FIG. 5,
and the description on them will be omitted.
[0093] In the drawing, reference numerals 36a and 36b denote
sensing terminals for taking out shunt currents of the
semiconductor devices, reference numerals 37a and 37b are
current-voltage conversion circuits as conversion means, reference
numerals 38a and 38b are short-circuit current detection circuits
as short-circuit current detection means of comparing the shunt
currents with the voltage value equivalent to the short-circuit
current, and reference numerals 39a and 39b are gate cut control
circuits as gate cut control means, which manages gate cut timing
and shutoff execution time, at the time of short-circuit current
detection.
[0094] Thus, in this embodiment, it is possible to prevent the
breakdown of the concerned semiconductor device beforehand and to
protect the semiconductor device from the short-circuit current by
monitoring the terminal of a shunt current of a current, which
flows in the semiconductor device, by focusing that the
semiconductor device for electric power conversion has parallel
arrangement inside its chip due to the configuration of an IGBT or
an MOSFET device, and by shutting off the gate control signal of
the semiconductor device concerned at the time of short-circuit
current generating.
[0095] Embodiment 8
[0096] FIG. 11 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to an eighth
embodiment of this invention. In addition, in FIG. 11, the same
numerals will be given to parts corresponding to those in FIG. 5,
and the description on them will be omitted.
[0097] In the drawing, reference numerals 36a and 36b denote
sensing terminals for taking out shunt currents of the
semiconductor devices similarly to the above, and reference
numerals 40a and 40b denote current-voltage conversion circuits as
conversion means, which may be also used as the above-described
current-voltage conversion circuit 37. Reference numerals 41a and
41b denote overcurrent detection circuits as overcurrent detection
means of comparing them with voltage values equivalent to an
overcurrent, and reference numerals 42a and 42b denote di/dt
control circuits which dull the current interception velocity of
the semiconductor devices at the time of overcurrent detection.
[0098] Next, with reference to FIG. 12, di/dt control will be
described by taking IGBT drive as an example.
[0099] In FIG. 12, reference numeral 101 denotes, for example, a
gate drive command signal after waveform shaping that is outputted
from the gate signal output means shown in FIG. 11, i.e., the gate
drive signal waveform shaping circuit 26. Reference numerals 102a
and 103a denote an IGBT gate voltage waveform and a
collector-emitter voltage waveform at the time of di/dt control not
operating. Similarly, reference numerals 102b and 103b denote an
IGBT gate voltage waveform and an collector-emitter voltage
waveform at the time of di/dt control operating.
[0100] Generally, it is required that the gate drive command signal
101 has variation speed as fast as possible to an IGBT gate in many
cases for the purpose of loss reduction by making the switching
frequency high. On the other hand, since the variation speed of a
gate drive command, i.e., the variation speed of a collector
current appears as a switching surge voltage by the product with an
inductance component which exists on a path of the collector
current, the variation speed of a collector current is restricted
by a withstand voltage of the semiconductor device, the withstand
voltages of other electronic components which are attached on the
same system. Therefore, the variation speed of the gate drive
command signal is prescribed by characteristics of the
semiconductor device and the configuration of an applied
system.
[0101] A di/dt control function is activated by the overcurrent
detection circuit 41 detecting that the collector current increases
under the above-mentioned short circuit detection current and
beyond the specified value, and dulls the off speed of the gate
drive signal like the signal 102b. Thereby, the shutoff speed of
the collector current and the return speed 103b of the
collector-emitter voltage also become dull. The switching surge
voltage proportional to the product of a current variation speed
and a current path inductance as a result is reduced, and an excess
of a withstand voltage by the surge voltage rise at the time of
overcurrent is prevented.
[0102] Thus, in this embodiment, it becomes possible to suppress a
surge voltage generated at the time of switching and to prevent the
excess of the withstand voltage due to the rise of the surge
voltage at the time of overcurrent by monitoring the
above-described shunt current as an overcurrent protective function
of a semiconductor device for electric power conversion, switching
a circuit so that the gate resistance of the semiconductor device
may become large without shutting off the switching operation of
the semiconductor device with limiting to a case that the shunt
current is less than short-circuit current and more than the
maximum current which flows in the semiconductor device, and
suppressing di/dt.
[0103] Embodiment 9
[0104] FIG. 13 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to a ninth
embodiment of this invention. In addition, in FIG. 13, the same
numerals will be given to parts corresponding to those in FIG. 10,
and the description on them will be omitted.
[0105] In the drawing, reference numerals 43a and 43b denote gate
short-circuit detection circuits as gate short-circuit detection
means which detects exclusive OR of logic levels of the inputted
gate drive signal, and the gate terminal voltage of the
semiconductor device, and if both logic levels differ from each
other, the gate shutoff control means 39a and 39b shut off the gate
control signal of the semiconductor device concerned.
[0106] Thus, in this embodiment, it becomes possible to prevent the
breakdown of the semiconductor device concerned beforehand, as the
gate signal short-circuit protection apparatus for an semiconductor
device for electric power conversion, by comparing the voltage
logic level of the gate input signal of a semiconductor device
drive circuit, i.e., the gate drive signal from an external control
unit with the voltage logic level of the gate terminal of the
semiconductor device, and shutting off the semiconductor device if
not coinciding, that is, shutting off the gate control signal of
the semiconductor device concerned at the time of the gate
short-circuit of the semiconductor device.
[0107] Embodiment 10
[0108] FIG. 14 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to a tenth
embodiment of this invention. In addition, in FIG. 14, the same
numerals will be given to parts corresponding to those in FIG. 10,
and the description on them will be omitted.
[0109] In the drawing, reference numerals 44a and 44b denote gate
voltage detecting circuits, and reference numerals 45a and 45b
denote gate voltage abnormality determination circuits.
[0110] The gate voltages of the semiconductor devices are detected
by the gate voltage detection circuits 44a and 44b, which are
compared with the voltage for gate voltage abnormality
determination set by the gate voltage abnormality determination
circuit 45 as gate voltage abnormality determination means, and if
abnormal, the current flow in the semiconductor device is shut
off.
[0111] Thus, in this embodiment, it becomes possible to prevent the
overvoltage breakdown of a gate if a power supply voltage for
driving the gate of each semiconductor device generated in the
power supply circuit exceeds a specified upper limit voltage as an
abnormality of the gate voltage by monitoring whether the power
supply voltage is lower or higher than a rated voltage, as a gate
voltage abnormality protective function of the semiconductor device
for electric power conversion, and it becomes possible to let
performance deterioration caused by heat increase of the concerned
semiconductor device known if the power supply voltage becomes
lower than a specified minimum voltage.
[0112] Embodiment 11
[0113] In this embodiment, so as to prevent the overvoltage
breakdown of the concerned semiconductor device which is caused by
the surge voltage at the time of switching shutoff, by using
together the di/dt control circuit, proposed in the above-described
eighth embodiment, at the time of gate signal shutoff operation by
any one of the overheat protective function proposed in the
above-described fifth embodiment, the short-circuit current
protective function proposed in the above-described seventh
embodiment, and the gate short-circuit protective function proposed
in the above-described ninth embodiment, the current shutoff speed
of the semiconductor device concerned is dulled.
[0114] Thus, in this embodiment, it is possible to suppress the
surge voltage at the time of shutoff by suppressing the di/dt of
the semiconductor device through switching a circuit so that gate
resistance of the semiconductor device may become large when the
semiconductor device is shut off in all the protective functions
for the semiconductor device for electric power conversion. Hence,
it is possible to prevent beforehand the secondary calamity leading
to the overvoltage breakdown of the device.
[0115] Embodiment 12
[0116] FIG. 15 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to a twelfth
embodiment of this invention. In addition, in FIG. 15, the same
numerals will be given to parts corresponding to those in FIG. 11,
and the description on them will be omitted.
[0117] In the drawing, reference numerals 46a and 46b denote
protective function control means, reference numeral 47 denotes
protective function operating state output means, and reference
numeral 48 denotes all phase gate signal shutoff means. The
protective function control means 46a and 46b include the overheat
protective function shown in the above-described fifth embodiment,
the short-circuit current protective function shown in the
above-described seventh embodiment, the overcurrent protection
function shown in the above-described eighth embodiment, and the
gate short-circuit protective function shown in the above-described
ninth embodiment.
[0118] If any one of the above-described protective functions
operates and performs shutoff operation of the gate control signal
of the corresponding phase, the protective function control means
46a and 46b transmit to the protective function operating state
output means 47 which protective function is operating. The
protective function operating state output means 47 has a function
of outputting to an external control unit, which is not shown, what
kind of a protective function shuts the semiconductor device while
simultaneously shutting off the gate control signals of all phases
by all phase gate signal shutoff means 48 except the phase where a
gate control signal is shut off by the concerned protective
function operating.
[0119] Thus, in this embodiment, in all the protective functions of
the semiconductor device for electric power conversion, the gate
input signals of all the semiconductor devices except the
semiconductor device concerned is compulsorily shut off when any of
the semiconductor device is shut off by a protective function, and
it is outputted via serial communication or in a logic signal or
the like that is converted into a voltage level on the basis of a
low voltage power supply reference to an external control unit that
any one of the semiconductor devices is shut off. Hence, it is
possible to protect the electric power conversion apparatus, and in
extension, the whole inverter apparatus, and hence, to prevent a
secondary calamity beforehand.
[0120] Embodiment 13
[0121] FIG. 16 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to a thirteenth
embodiment of this invention. In addition, in FIG. 16, the same
numerals will be given to parts corresponding to those in FIG. 5,
and the description on them will be omitted.
[0122] In the drawing, reference numeral 50 denotes a high voltage
power supply input circuit as a voltage dividing circuit dividing
high voltage power, reference numeral 51 denotes a microcomputer,
reference numeral 52 denotes an A/D converter port, reference
numeral 53 denotes a map interpolating operation means, and
reference numeral 54 denotes information storage means. In
addition, reference numeral 55 denotes insulated transmission means
as output means, reference numeral 56 denotes digital data output
means, reference numeral 57 denotes serial communication means,
reference numeral 58 denotes overvoltage determination means, and
reference numeral 59 denotes a D/A conversion circuit.
[0123] Next, operation will be described.
[0124] After performing voltage division and waveform shaping of an
input voltage of a high voltage power supply, the high voltage
power supply input circuit 50 inputs it into the A/D converter port
52 of the microcomputer 51, and obtains a high power supply voltage
as an A/D conversion value. A map for obtaining a desired
conversion characteristic (hereafter, a conversion characteristic
map) is stored beforehand in the microcomputer 51, and a target
output value is obtained from the A/D conversion value by the map
interpolating operation means 53. Here, the meaning of preparing
the conversion characteristic map is not only to process input
voltage characteristics into arbitrary output voltage
characteristics (convert characteristics), but also to make the
output voltage value more accurate to the inputted high power
supply voltage.
[0125] After obtaining the electric insulation of the high power
supply voltage value after the characteristic conversion, which is
obtained, by the insulated transmission means 55, then electric
power conversion apparatus 19 outputs an analog voltage, which is
the power supply reference on which the external system concerned
is working, through the D/A conversion circuit 59 to the system
(for example, a control unit giving a control signal to this
apparatus) that is not shown and is arranged out of the electric
power conversion apparatus 19, or outputs it as digital data via
the serial communication means 57.
[0126] In addition, this embodiment is for performing electric
insulation (reference power supply conversion) processing in the
phase of digital information regardless of output forms such as
analog voltage output or digital signal output, which is digitally
converted, at the time of supplying the information to a system
having a different reference power supply. Hence, since it becomes
unnecessary to consider insulating operation from a high voltage
power supply in all the equipment that operates on the basis of a
low voltage power supply reference and is connected to this
apparatus, it is possible to miniaturize each equipment.
[0127] Thus, this embodiment reads the voltage between P and N,
which is a high power supply voltage, into a microcomputer by A/D
conversion processing, converts the voltage into a voltage level on
the basis of a low voltage power supply reference for an external
control unit, and outputs it via serial communication, in an analog
signal, or the like. Hence, since it becomes unnecessary to
consider insulating operation from a high voltage power supply in
all the equipment that operates on the basis of a low voltage power
supply reference, it is possible to miniaturize each equipment.
[0128] Embodiment 14
[0129] FIG. 17 is a block diagram showing a circuit configuration
of an electric power conversion apparatus according to a fourteenth
embodiment of this invention. In addition, in FIG. 17, the same
numerals will be given to parts corresponding to those in FIG. 16,
and the description on them will be omitted.
[0130] In the drawing, reference numeral 60 denotes an adjusting
device as adjusting means. The adjusting device 60 is connected to
the electric power conversion apparatus 19 during an outgoing
inspection step of the electric power conversion apparatus 19.
[0131] Here, a method of correcting a voltage map will be
described.
[0132] The adjusting device 60 makes the electric power conversion
apparatus 19 recognize that the process is at an outgoing
inspection step, with using a recognition method with specified
information transmission via the serial communication means 57, or
a recognition method with a specified voltage pattern input to the
high voltage power supply input circuit 50. The adjusting device 60
inputs a specified high voltage to the electric power conversion
apparatus 19, and obtains the data, which the microcomputer 51
reads at the A/D converter port 52, by making the data outputted
with using the serial communication means 57.
[0133] At the same time, the adjusting device 60 obtains a voltage
equivalent to the A/D conversion result from the microcomputer 51
by making the data outputted from the digital data output means 56.
The adjusting device 60 can obtain the correlation characteristics
among the high voltage value (VPN) applied to the electric power
conversion apparatus 19, the digital data (VAD) that is the result
by the microcomputer 51 performing A/D conversion, and the actual
analog output voltage (VAN) at the time of the microcomputer 51
outputting the voltage equivalent to an A/D conversion value, by
repeating the same steps about a plurality of high voltage points.
According to the above correction means, it becomes possible to
extremely decrease a measurement error resulting from the accuracy
and linearity of electronic components by obtaining both of the
actual high voltage input value and the actual A/D conversion
result which the macro computer obtains.
[0134] In consequence, the adjusting device 60 obtains the
conversion characteristic map for a digital data output, where the
arbitrary processing of the input voltage characteristics and the
high accuracy of the output value to the high power supply voltage
inputted are made to be compatible, from the VPN-VAD
characteristics. Similarly, the adjusting device 60 obtains the
characteristic conversion map for an analog voltage output from the
VPN-VAD characteristics, and the VAD-VAN characteristics. The
adjusting device 60 makes the information storage means 54,
incorporated in electric power conversion apparatus 19, store the
characteristic conversion maps.
[0135] As this storage method, it is also good to directly write
the maps from the adjusting device 60, or it is also good to
transmit the maps to the microcomputer 51, incorporated in the
electric power conversion apparatus 19, with using the serial
communication means 57 etc., and to make the microcomputer 51 write
the maps. Thereby, since an external control circuit can monitor a
high power supply voltage by a signal on the basis of a low voltage
power supply reference, electric insulating operation from a high
power supply voltage becomes unnecessary, and hence optimal layout
in the improvement of EMI-proof property, or a safety aspect
becomes possible.
[0136] Thus, in this embodiment, by providing the interpolating
operation means of storing beforehand the conversion value of the
high voltage power supply in two or more points in a microcomputer
as map data at the time of shipment in order to correct the
dispersion of electronic component characteristics in a conversion
circuit at the time of performing the A/D conversion processing of
the high voltage power supply at the microcomputer, it is possible
to provide a high power supply voltage monitoring circuit excellent
in voltage measurement accuracy and linearity without using highly
accurate electronic components.
[0137] Embodiment 15
[0138] The circuit configuration of this embodiment is not shown,
but what is the same as that in the above-described thirteenth
embodiment (circuit configuration of FIG. 16) is used, and the
adjusting device 60 described in the above-described fourteenth
embodiment is connected to this.
[0139] At the time of creating characteristic conversion maps, the
above-described adjusting device 60 calculates an overvoltage
determination value from the known overvoltage determination
standard value, and makes the information storage means 54,
incorporated in electric power conversion apparatus 19, store the
overvoltage determination value.
[0140] The electric power conversion apparatus 19 comprises means
for comparing an A/D conversion value of a divided value of the
high power supply voltage with an overvoltage determination value
stored beforehand in microcomputer 51, that is, overvoltage
determination means 58. Hence, in order to protect the overvoltage
breakdown of all the components mounted in an inverter apparatus,
if an overvoltage level is exceeded, the electric power conversion
apparatus 19 not only shut off a semiconductor device with
suppressing the switching speed (di/dt characteristic) of the
semiconductor device, but also makes an external control unit know
that the semiconductor device is shut off, by abnormality
occurrence signal output means such as the serial communication
means 57 where it is converted into the voltage level on the basis
of the low voltage power supply reference.
[0141] Thus, in this embodiment, as the overvoltage protection of
all the components mounted in an inverter apparatus, the electric
power conversion apparatus 19 not only shuts off all semiconductor
devices by suppressing the di/dt of the semiconductor device for
electric power conversion if the high power supply voltage between
P and N exceeds the overvoltage level beforehand set in the
microcomputer, but also outputs to an external control unit that
the semiconductor devices are shut off, via serial communication,
where it is converted into the voltage level on the basis of the
low voltage power supply reference, or in a logic signal, or the
like. Hence, it is possible to prevent beforehand the overvoltage
breakdown of high voltage components other than the semiconductor
device for electric power conversion that are mounted in the
inverter apparatus, for example, a DC voltage smoothing
capacitor.
[0142] As described above, according to this invention, since a
power supply circuit for supplying power to a drive and protection
circuit of a semiconductor device for electric power conversion can
be made to be integrated in the same module, the miniaturization
and weight reduction of an electric power conversion apparatus, and
in extension, the miniaturization of an inverter apparatus itself
are attained.
[0143] In addition, by integrating the power supply circuit
contained in another case up to now, it becomes possible not only
to reduce a wire harness, but also to sharply reduce noise
superimposed on power supply lines from the external. Hence, it is
possible to improve system reliability in the use under a harsh
environment like a vehicle-mounted application.
[0144] In addition, since all the signals of a high voltage power
supply system are processed within the electric power conversion
apparatus, all signals to an external control unit are only those
based on a low voltage power supply reference. That is, since
electric isolation of the high voltage power supply system from the
low voltage power supply system is clear, this becomes most
desirable inverter apparatus structure in safety in a system where
the low voltage power supply system like a vehicle-mounted
application is made to be common with the car body ground.
[0145] Furthermore, since the chip temperature of the semiconductor
device for electric power conversion can be read in high precision
and high response with using an on-chip temperature sensor, it
becomes possible to use the semiconductor device for electric power
conversion up to its full electric rating.
[0146] Moreover, the exact temperature of the semiconductor device
for electric power conversion is outputted to an external control
circuit. Hence, it is possible to suppress the heat generation of
the semiconductor device for electric power conversion by
suppressing the torque of a three phase motor, i.e., a motor line
current by an external control circuit before an overheat
protective function works, and hence it is possible to prevent a
system halt by the overheat protective function beforehand.
[0147] In addition, it is possible to protect the electric power
conversion apparatus, and in extension, the entire inverter
apparatus, and to prevent the leading to a secondary calamity by
shutting off the semiconductor device for electric power conversion
even if the electric power conversion apparatus malfunctions due to
a certain factor.
[0148] Furthermore, it is effective for trouble shooting at the
time of corrective maintenance to store diagnosis information,
which is the contents of malfunctions, in the external control
circuit.
[0149] Moreover, the state where overcurrent is flowing in the
semiconductor device for electric power conversion is outputted to
an external control circuit due to a certain factor. Hence, it is
possible to suppress the heat generation of the semiconductor
device for electric power conversion by suppressing the torque of a
three phase motor, i.e., a motor line current by the external
control circuit before an overheat protective function or
short-circuit current protection works, and hence it is possible to
prevent a system halt by the protective function beforehand.
[0150] In addition, since an external control circuit can monitor
the high power supply voltage by a signal on the basis of a low
power supply voltage reference, electric insulating operation from
the high power supply voltage becomes unnecessary, and an optimal
layout in the improvement of EMI-proof property and safety becomes
possible.
[0151] Furthermore, it is possible to prevent beforehand the
overvoltage breakdown of high voltage components other than the
semiconductor device for electric power conversion that are mounted
in an inverter apparatus, such as a DC voltage smoothing
capacitor.
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